Our dig starts Saturday and today when we met with the pool builder he said there is no reason to get a robot that clean walls?? He said it was hard on them and causes more issues. He has the regular Hayward Sharkvac and I was looking at ordering online the Dolphin Nautilus Plus for the same price. I'm having a hard time thinking I don't need something to clean walls! He also threw out there that we would have to send our robot to be fix where his we could just take to him to fix. Thoughts on this would be great! Thanks!!